KR20080042810A - Indole compound, optical filter and optical recording material - Google Patents

Abstract

Disclosed is an indole compound represented by the following general formula (I). (I) (In the formula, R1 and R2 independently represent a hydrogen atom, a hydrocarbon group having 1-30 carbon atoms or a substituent represented by the general formula (II) below; R3 and R4 independently represent an alkyl group having 1-10 carbon atoms, an alkoxy group having 1-10 carbon atoms, or an aryl group having 6-30 carbon atoms; R5, R6, R7 and R8 independently represent a hydrogen atom, a hydrocarbon group having 1-30 carbon atoms, a halogen atom, a hydroxyl group, a nitro group, a cyano group, or NHR or NR'R'' wherein R, R' and R'' independently represent an alkyl group having 1-10 carbon atoms and R' and R'' may combine together to form a ring, and R5 and R6, R6 and R7, and R7 and R8 may respectively combine together to form a ring; Anq- represents a q-valent anion and q represents 1 or 2; and p represents a coefficient required for neutralizing the electrical charge.

Description

Indole compound, optical filter and optical recording material {INDOLE COMPOUND, OPTICAL FILTER AND OPTICAL RECORDING MATERIAL}

The present invention relates to novel indole compounds, optical filters and optical recording materials. The indole compound is useful as an optical element or the like. The indole compound is particularly useful as an ultraviolet absorber to be included in an optical filter for an image display device, and has an optical recording medium capable of high-density optical recording and reproducing by a low energy laser or the like having a wavelength in the visible and near infrared region. It is useful for optical recording materials used for

Optical recording media generally have a large recording capacity and are widely used for having excellent characteristics such as recording or reproducing in a non-contact manner. In write-once optical discs such as WORM, CD-R, DVD-R, etc., a laser is focused on a very small area of the optical recording layer, and the characteristics of the optical recording layer are changed and recorded. Playback is performed due to the difference in the amount of reflected light between the and unrecorded portions.

At present, in the above optical disk, the wavelength of the semiconductor laser used for recording and reproduction is 750 nm to 830 nm in CD-R and 620 nm to 690 nm in DVD-R. In order to realize further increase in capacity, Optical discs using short wavelength lasers have been studied. For example, the use of 380-420 nm light as recording light has been studied.

In the optical recording medium for short wavelength laser, various compounds are used for formation of an optical recording layer. For example, an azo compound is reported in Patent Document 1, a porphyrin compound is reported in Patent Document 2, and a metal complex of a triazole compound is reported in Patent Document 3. However, these compounds do not necessarily have suitable absorption wavelength characteristics as the optical recording material used for forming the optical recording layer.

On the other hand, in an optical filter for an image display device such as a liquid crystal display (LCD), a plasma display panel (PDP), an electroluminescent display (ELD), a cathode ray tube display (CRT), a fluorescent display tube, a field emission display, and the like. The compound which absorbs the light of the wavelength of 300-390 nm is used as an ultraviolet absorber.

For example, the following patent document 4 reports the filter for organic electroluminescent display elements containing a ultraviolet absorber and blocking the light of 200-410 nm. However, the ultraviolet absorber used for this organic EL display element filter was not necessarily suitable as the ultraviolet absorber for optical filters.

[Patent Document 1] Japanese Patent Publication No. 2004-209771

[Patent Document 2] Japanese Patent Publication No. 2004-58365

[Patent Document 3] Japanese Patent Publication No. 2004-174838

[Patent Document 4] Japanese Patent Publication No. 2004-102223

It is therefore an object of the present invention to provide a compound having optical properties suitable for an optical element used in an optical recording material for an optical filter for an image display device and an optical recording medium for short wavelength laser light, in particular.

As a result of extensive studies, the inventors have found that a specific indole compound having an imino structure has an absorption wavelength characteristic that satisfies the optical element.

SUMMARY OF THE INVENTION The present invention has been made on the basis of the above findings, and includes an indole compound represented by the following general formula (I), an optical filter containing the indole compound, and an optical recording layer of an optical recording medium having an optical recording layer formed on a substrate. An optical recording material comprising the indole compound used is provided.

(In formula, R <^1> and R <^2> respectively independently represents a hydrogen atom, a hydrocarbon group of 1-30 carbon atoms, or a substituent represented by the following general formula (II), R <^3> and R <^4> respectively independently, An alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or an aryl group having 6 to 30 carbon atoms, and R ⁵ , R ⁶ , R ⁷ and R ⁸ each independently represent a hydrogen atom and carbon; A hydrocarbon group having 1 to 30 atoms, a halogen atom, a hydroxyl group, a nitro group, a cyano group, NHR or NR'R '', and each of R, R 'and R''is independently 1 to 10 carbon atoms. An alkyl group, R 'and R''may be linked to each other to form a ring, and R ⁵ and R ⁶ , R ⁶ and R ⁷ , R ⁷ and R ⁸ may be linked to each other to form a ring; An ^{q -} represents q valent anion, q represents 1 or 2, p represents the coefficient of maintaining charge neutral.

(Wherein, R ^a to R ⁱ each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, the methylene group in the alkyl group may be substituted with -O- or -CO-, and Z is a direct bond or It represents an alkylene group having 1 to 8 carbon atoms which may have a substituent, and the methylene group in the alkylene group is -O-, -S-, -CO-, -CO0-, -OC0-, -S0 _2- , -NH -, -CONH-, -NHC0-, -N = CH- or -CH = CH- may be substituted, and M represents a metal atom.)

EMBODIMENT OF THE INVENTION Hereinafter, the optical filter and optical recording material which contain the indole compound of this invention and the said indole compound are demonstrated in detail based on preferable embodiment.

First, the indole compound of the present invention will be described.

In the indole compound of the present invention represented by the general formula (I), as the hydrocarbon group having 1 to 30 carbon atoms represented by R ¹ , R ² , R ⁵ , R ⁶ , R ⁷ and R ⁸ , methyl, Ethyl, propyl, isopropyl, butyl, secondary butyl, tertiary butyl, isobutyl, amyl, isoamyl, tertiary amyl, hexyl, cyclohexyl, cyclohexylmethyl, 2-cyclohexylethyl, heptyl, isoheptyl, first Alkyl groups such as 3heptyl, n-octyl, isooctyl, tertiary octyl, 2-ethylhexyl, nonyl, isononyl, decyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, Vinyl, 1-methylethenyl, 2-methylethenyl, propenyl, butenyl, isobutenyl, pentenyl, hexenyl, heptenyl, octenyl, decenyl, pentadecenyl, 1-phenylpropene-3- Alkenyl groups such as one, phenyl, naphthyl, 2-methylphenyl, 3-methylphenyl, 4-methylphenyl, 4-vinylphenyl, 3-isopropylphenyl, 4-isopropylphenyl, 4-butylphenyl, 4-isobutylphenyl , 4-Part 3 Phenyl, 4-hexylphenyl, 4-cyclohexylphenyl, 4-octylphenyl, 4- (2-ethylhexyl) phenyl, 4-stearylphenyl, 2,3-dimethylphenyl, 2,4-dimethylphenyl, 2, Alkyl aryl groups, such as 5-dimethylphenyl, 2, 6- dimethylphenyl, 3, 4- dimethylphenyl, 3, 5- dimethylphenyl, 2, 4- di- tert-butylphenyl, and cyclohexylphenyl, benzyl, phenethyl, 2 Arylalkyl groups such as -phenylpropan-2-yl, diphenylmethyl, triphenylmethyl, styryl, cinnamil, and the like, and those interrupted at ether bonds and / or thioether bonds, for example 2-methoxyethyl , 3-methoxypropyl, 4-methoxybutyl, 2-butoxyethyl, methoxyethoxyethyl, methoxyethoxyethoxyethyl, 3-methoxybutyl, 2-phenoxyethyl, 3-phenoxypropyl , 2-methylthioethyl, 2-phenylthioethyl, and the like. In addition, these groups may be substituted by an alkoxy group, an alkenyl group, a nitro group, a cyano group, a halogen atom, etc., and when substituted by one or more types selected from an alkoxy group, an alkenyl group, and a cyano group, the whole including these substituents Has up to 30 carbon atoms.

Examples of the alkyl group having 1 to 10 carbon atoms represented by R ³ , R ⁴ , R, R ', and R''in the general formula (I) include methyl, ethyl, propyl, isopropyl, butyl, and second butyl. , Tert-butyl, isobutyl, amyl, isoamyl, tert-amyl, hexyl, cyclohexyl, heptyl, isoheptyl, tertiary heptyl, n-octyl, isooctyl, tert-octyl, 2-ethylhexyl, nonyl, decyl Examples of the alkoxy group having 1 to 10 carbon atoms include methyloxy, ethyloxy, isopropyloxy, propyloxy, butyloxy, pentyloxy, isopentyloxy, hexyloxy, heptyloxy, octyloxy, 2-ethylhexyloxy etc. are mentioned, As an aryl group of 6-30 carbon atoms, phenyl, naphthyl, 2-methylphenyl, 3-methylphenyl, 4-methylphenyl, 4-vinylphenyl, 3-isopropylphenyl , 4-isopropylphenyl, 4-butylphenyl, 4-isobutylphenyl, 4-tertbutylphenyl, 4-hexylphenyl, 4-cyclohexylphenyl, 4-octylphenyl, 4- (2-ethylhexyl) phenyl , 4-stearylphenyl, 2,3- Methylphenyl, 2,4-dimethylphenyl, 2,5-dimethylphenyl, 2,6-dimethylphenyl, 3,4-dimethylphenyl, 3,5-dimethylphenyl, 2,4-dize-3butylphenyl, 2,5- Di-tert-butylphenyl, 2,6-di-tert-butylphenyl, 2,4-di-tert-pentylphenyl, 2,5-di-tertyl amylphenyl, 2,5-di-tert-octylphenyl, 2,4-dicumylphenyl , Cyclohexylphenyl, biphenyl, 2,4,5-trimethylphenyl, benzyl, phenethyl, 2-phenylpropan-2-yl, diphenylmethyl, triphenylmethyl, styryl, cinnamil and the like.

Examples of the halogen atom represented by R ⁵ , R ⁶ , R ⁷ and R ⁸ in General Formula (I) include fluorine, chlorine, bromine and iodine.

Examples of the ring in which R 'and R''in General Formula (I) are linked to each other include a piperidine ring, a piperazine ring, a pyriridine ring, a morpholine ring, and the like. R ⁵ and R ⁶ As a ring formed by connecting R <^6> and R <^7> and R <^7> and R <^8> , a cyclobutene ring, a cyclopentene ring, a cyclohexene ring, a benzene ring, a pyridine ring, etc. are mentioned.

Examples of the alkyl group having 1 to 4 carbon atoms represented by R ^a to R ⁱ in General Formula (II) include methyl, ethyl, propyl, isopropyl, butyl, second butyl, third butyl, isobutyl, and Methoxy, ethoxy, propyloxy, isopropyloxy, methoxymethyl, ethoxymethyl, 2-methoxyethyl, acetyl, 1-carbonylethyl, acetylmethyl, 1-carbonylpropyl, 2-oxobutyl, 2- Acetyl ethyl, 1-carbonyl isopropyl, etc. are mentioned, As a C1-C8 alkylene group which may have a substituent represented by Z, methylene, ethylene, propylene, methyl ethylene, butylene, 1-methyl Propylene, 2-methylpropylene, 1,2-dimethylpropylene, 1,3-dimethylpropylene, 1-methylbutylene, 2-methylbutylene, 3-methylbutylene, 4-methylbutylene, 2,4-dimethyl Butylene, 1,3-dimethylbutylene, pentylene, hexylene, heptylene, octylene, ethane-1,1-diyl, propane-2,2-diyl, ethenylene, propenylene, methyleneoxy, ethyl Oxy, oxymethylene, thiomethylene, carbonylmethylene, carbonyloxymethylene, methylenecarbonyloxy, sulfonylmethylene, aminomethylene, acetylamino, ethylenecarboxyamide, ethaneimideyl and the like, and are represented by M Examples of metal atoms include iron, cobalt, nickel, copper, zinc, aluminum, titanium, zirconium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, osmium, manganese, ruthenium, gallium, indium, silicon, germanium, tin, antimony, Bismuth, gold, silver, palladium, rhodium, platinum, iridium, yttrium, lanthanum, praseodymium, neodymium, promethium, gadolinium, dysprosium, holmium, lutetium, scandium and the like.

In the general formula (I), examples of the anion represented by An ^{q −} include halogen anions such as chlorine anion, bromine anion, iodine anion, and fluorine anion as monovalent ones; Inorganic anions such as perchlorate anion, chlorate anion, thiocyanate anion, phosphorus hexafluoride anion, antimony hexafluoride anion, and boron tetrafluoride anion; Benzenesulfonic acid anion, toluenesulfonic acid anion, trifluoromethanesulfonic acid anion, diphenylamine-4-sulfonic acid anion, 2-amino-4-methyl-5-chlorobenzenesulfonic acid anion, 2-amino-5-nitrobenzenesulfonic acid anion, etc. Organic sulfonic acid anion; Organic phosphate anions such as octyl phosphate anion, dodecyl phosphate anion, octadecyl phosphate anion, phenyl phosphate anion, nonylphenyl phosphate anion, and 2,2'-methylenebis (4,6-di- tert-butylphenyl) phosphonic anion; Bistrifluoromethylsulfonylimide anion, bisperfluorobutanesulfonylimide anion, perfluoro-4-ethylcyclohexanesulfonate anion, tetrakis (pentafluorophenyl) boric anion, tris (fluoro Alkyl sulfonyl) carbo anion etc. are mentioned, As a bivalent thing, a benzen disulfonic acid anion, a naphthalenedisulfonic acid anion, etc. are mentioned, for example. In addition, a carboxyl group, a phosphonic acid group, a sulfonic acid group, etc. may be added to a quencher anion or cyclopentadienyl ring having a function of de-exciting (quenching) active molecules in an excited state. Metallocene compound anions, such as ferrocene and luteose, which have an anionic group, can also be used as necessary.

As said quencher anion, it is represented by the following general formula (A), (B) or following formula (C), for example, Unexamined-Japanese-Patent No. 60-234892, Unexamined-Japanese-Patent No. 5-43814. Japanese Patent Laid-Open No. 5-305770, Japanese Patent Laid-Open No. 6-239028, Japanese Patent Laid-Open No. 9-309886, Japanese Patent Laid-Open No. 9-323478, Japanese Patent Japanese Patent Laid-Open No. 10-45767, Japanese Patent Laid-Open No. 11-208118, Japanese Patent Laid-Open No. 2000-168237, Japanese Patent Laid-Open No. 2002-201373, Japanese Patent Laid-Open No. 2002-206061, Japan Anion as described in Unexamined-Japanese-Patent No. 2005-297407, Unexamined-Japanese-Patent No. 7-96334, international publication 98/29257, etc. are mentioned.

^Wherein X represents a nickel atom or a copper atom, and R ⁹ and R ¹⁰ each independently represent a halogen atom, an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 30 carbon atoms, or -SO _2- Represents a G group, G represents an aryl group, a dialkylamino group, a diarylamino group, a piperidino group, or a morpholino group which may be substituted with an alkyl group or a halogen atom, and a and b each represent 0 to 4. R ^ll , R ¹² , R ¹³ and R ¹⁴ each independently represent an alkyl group, an alkylphenyl group, an alkoxyphenyl group or a halogenated phenyl group.)

Among the indole compounds of the present invention, in general formula (I), R ¹ is a hydrocarbon group having 1 to 30 carbon atoms, especially an alkyl group having 1 to 8 carbon atoms or an aryl group having 6 to 13 carbon atoms; R ² is a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms, in particular a hydrogen atom, an alkyl group having 1 to 8 carbon atoms or an aryl group having 6 to 13 carbon atoms; R ³ is an alkyl group having 1 to 10 carbon atoms, particularly an alkyl group having 1 to 4 carbon atoms; R ⁴ is preferably an alkyl group having 1 to 10 carbon atoms, particularly an alkyl group having 1 to 4 carbon atoms, because it is excellent in terms of cost and optical properties.

Therefore, the following compound Nos. 1-24 are mentioned as a specific example of the indole compound of this invention.

The indole compound of the present invention represented by the above general formula (I) is not particularly limited in its production method, and can be obtained by a method using a well-known general reaction. As the production method, for example, an indole having a monovalent anion When obtaining a compound, the synthesis | combining method like the route shown in following [Formula 6] is mentioned.

(Wherein R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ are the same as the general formula (I), Hal represents a halogen atom, and D ⁻ represents an anion). .)

The indole compound of the present invention is useful as an optical element that exhibits a function by absorbing light having a specific wavelength, particularly at a wavelength of 320 to 420 nm. As an example of an optical element, the optical recording agent etc. which are used for formation of the optical recording layer of optical recording media, such as an ultraviolet absorber and an optical disk which are contained in an optical filter, are mentioned.

In addition to the optical element, the indole compound of the present invention may be used in synthetic intermediates such as pharmaceuticals, pesticides, flavorings, dyes, or various functional materials.

Next, the optical filter of this invention is demonstrated.

The optical filter of the present invention contains the indole compound of the present invention. Since the indole compound of the present invention has an absorption maximum wavelength of 340 to 390 nm, and can absorb and block ultraviolet rays of 410 nm or less and some visible light, the optical filter of the present invention containing the indole compound of the present invention is a display image. It is particularly suitable as an optical filter for an image display device to be used for high quality. The optical filter of the present invention can be used not only for an image display device but also for various applications such as analytical device, semiconductor device manufacture, astronomical observation, optical communication, and spectacle lens.

The optical filter of the present invention is usually arranged in front of the display. For example, the optical filter of the present invention may be directly attached to the surface of the display, or may be attached to the front side (outside) or the rear side (display side) of the front plate when the front plate is provided in front of the display.

As a typical structure of the optical filter of this invention, what provided each layer, such as a supercoat layer, an antireflection layer, a hard coat layer, a lubrication layer, in the transparent support body as needed. As a method of including in the optical filter of the present invention an optional component such as an indole compound of the present invention, a dye compound other than the indole compound of the present invention, various stabilizers, and the like, for example, (1) a transparent support or any desired layer A method of incorporating, (2) a method of coating on a transparent support or any respective layer, (3) a method of incorporating an adhesive layer between any adjacent neighbors selected from a transparent support and any of each layer, (4) each Apart from the layer, a method of forming a light absorbing layer containing a light absorbing agent such as the indole compound of the present invention and the like can be given.

In the optical filter of the present invention, the amount of the indole compound of the present invention is usually 1 to 1000 mg / m 2, preferably 5 to 100 mg / m 2, per unit area of the optical filter. When the light absorbing effect cannot be sufficiently exhibited, and when used in excess of 1000 mg / m 2, the color tone of the filter may become too strong to reduce the display quality and the like, and the brightness may also decrease.

In order to use the indole compound of the present invention in the above-mentioned range per unit area of the optical filter, it is usually used as follows. For example, when making the optical filter containing the indole compound of this invention in an adhesive layer, Preferably it is 0.001-0.05 mass part and methyl ethyl ketone with respect to 100 mass parts of adhesives, such as an acryl-type adhesive, 40-500 mass parts of solvents, such as these, are added, and a varnish is created, this varnish is apply | coated to transparent support materials, such as PET film which carried out the back contact | contact | adherence process, and it hardens | cures, and the adhesive layer (curing | curing of thickness 0.1-10 microns) Film) to obtain an optical filter.

As a method of incorporating the indole compound and the optional component of the present invention into the optical filter of the present invention, when the method of any of the above (1) to (4) is used, the blending ratio of each component is in accordance with the above blending ratio. do.

As a material of the said transparent support body, For example, inorganic materials, such as glass; Cellulose esters such as diacetyl cellulose, triacetyl cellulose (TAC), propionyl cellulose, butyryl cellulose, acetyl propionyl cellulose and nitrocellulose; Polyamides; Polycarbonate; Poly such as polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, poly-1,4-cyclohexanedimethylene terephthalate, polyethylene-1,2-diphenoxyethane-4,4'-dicarboxylate ester; polystyrene; Polyolefins such as polyethylene, polypropylene and polymethylpentene; Acrylic resins such as polymethyl methacrylate; Polysulfones; Polyether sulfone; Polyether ketones; Polyetherimide; Polymeric materials, such as polyoxyethylene and norbornene resin, are mentioned. The transmittance of the transparent support is preferably 80% or more, and more preferably 86% or more. It is preferable that haze is 2% or less, and it is more preferable that it is 1% or less. It is preferable that refractive index is 1.45-1.70.

In these transparent supports, infrared absorbers, inorganic fine particles, and the like can be added, and various surface treatments can be applied to the transparent supports.

Examples of the inorganic fine particles include layered clay minerals, silicon dioxide, titanium dioxide, barium sulfate, calcium carbonate and the like.

Examples of the various surface treatments include chemical treatment, mechanical treatment, corona discharge treatment, flame treatment, ultraviolet irradiation treatment, high frequency treatment, glow discharge treatment, active plasma treatment, laser treatment, and mixed acid treatment. And ozone oxidation treatment.

The primary coating layer is a layer used between the transparent support and the light absorbing layer when forming the light absorbing layer containing the light absorbing agent. The primary coating layer is a layer containing a polymer having a glass transition temperature of -60 to 60 ° C, a layer having a rough surface on the light absorbing layer side, or a layer containing a polymer having affinity with the polymer of the light absorbing layer. Form. In addition, the primary coating layer may be formed on the surface of the transparent support on which the light absorbing layer is not formed, and may be formed to improve the adhesion between the transparent support and the layer (for example, antireflection layer, hard coat layer) formed thereon, You may form in order to improve the affinity of the optical filter with the adhesive agent for bonding an optical filter and an image display apparatus. The thickness of the primer layer is preferably 2 nm to 20 μm, more preferably 5 nm to 5 μm, still more preferably 20 nm to 2 μm, even more preferably 50 nm to 1 μm, and 80 nm to 300 nm. Most preferred. The primary coating layer comprising a polymer having a glass transition temperature of -60 to 60 ° C. adheres the transparent support to the filter layer due to the adhesiveness of the polymer. Polymers having a glass transition temperature of -60 ° C to 60 ° C are, for example, vinyl chloride, vinylidene chloride, vinyl acetate, butadiene, neoprene, styrene, chloroprene, acrylic acid ester, methacrylic acid ester, acrylonitrile or methyl vinyl ether. It can be obtained by polymerization or copolymerization thereof. It is preferable that glass transition temperature is 50 degrees C or less, It is more preferable that it is 40 degrees C or less, It is more preferable that it is 30 degrees C or less, It is still more preferable that it is 25 degrees C or less, Most preferably, it is 20 degrees C or less. It is preferable that the elasticity modulus at 25 degrees C of a primary coating layer is 1-1000 Mpa, It is more preferable that it is 5-800 Mpa, It is most preferable that it is 10-500 Mpa. The primary coating layer having a rough surface on the light absorbing layer side forms a light absorbing layer on the rough surface, thereby adhering the transparent support and the light absorbing layer. The rough coat layer having a rough surface on the light absorbing layer side can be easily formed by application of a polymer latex. It is preferable that it is 0.02-3 micrometers, and, as for the average particle diameter of latex, it is more preferable that it is 0.05-1 micrometer. Examples of the polymer having affinity with the binder polymer of the light absorbing layer include acrylic resins, cellulose derivatives, gelatin, casein, starch, polyvinyl alcohol, soluble nylon and polymer latex. In the optical filter of the present invention, two or more primary coating layers may be formed. You may add the solvent which swells a transparent support body, a mat agent, surfactant, an antistatic agent, an application | coating adjuvant, a film-forming agent, etc. to a primary coating layer.

In the antireflection layer, a low refractive index layer is essential. The refractive index of the low refractive index layer is lower than that of the transparent support. It is preferable that it is 1.20-1.55, and, as for the refractive index of a low refractive index layer, it is more preferable that it is 1.30-1.50. It is preferable that it is 50-400 nm, and, as for the thickness of a low refractive index layer, it is more preferable that it is 50-200 nm. The low refractive index layer is made of a fluorinated polymer having a low refractive index (Japanese Patent Publication No. 57-34526, Japanese Patent Application Laid-Open No. 3-130103, Japanese Patent Publication No. Hei 6-115023, Japanese Patent Publication No. 8) -313702, Japanese Patent Application Laid-Open No. Hei 7-168004, layers obtained by the sol-gel method (Japanese Patent Application Laid-open No. Hei 5-208811, Japanese Patent Application Laid-open No. Hei 6-299091, Japanese Patent Application Laid-Open No. 7-168003) or a layer containing fine particles (Japanese Patent Publication No. 60-59250, Japanese Patent Publication No. Hei 5-13021, Japanese Patent Publication No. Hei 6-56478, Japanese Patent Publication 7-92306 and Japanese Patent Laid-Open No. Hei 9-288201). In the layer containing the fine particles, voids can be formed in the low refractive index layer as microvoids between the fine particles or in the fine particles. It is preferable that the layer containing microparticles | fine-particles has a porosity of 3-50 volume%, and it is more preferable to have a porosity of 5-35 volume%.

In order to prevent reflection of a wide wavelength range, in the said anti-reflection layer, it is preferable to laminate | stack a layer with a high refractive index (medium-high refractive index layer) in addition to a low refractive index layer. It is preferable that it is 1.65-2.40, and, as for the refractive index of a high refractive index layer, it is more preferable that it is 1.70-2.20. The refractive index of the medium refractive index layer is adjusted to be an intermediate value between the refractive index of the low refractive index layer and the refractive index of the high refractive index layer. It is preferable that it is 1.50-1.90, and, as for the refractive index of a medium refractive index layer, it is more preferable that it is 1.55-1.70. It is preferable that the thickness of a medium and high refractive index layer is 5 nm-100 micrometers, It is more preferable that it is 10 nm-10 micrometers, It is most preferable that it is 30 nm-1 micrometer. The haze of the medium-high refractive index layer is preferably 5% or less, more preferably 3% or less, and most preferably 1% or less. The medium and high refractive index layer can be formed using a polymer binder having a relatively high refractive index. Examples of the polymer having a high refractive index include polystyrene, styrene copolymers, polycarbonates, melamine resins, phenol resins, epoxy resins, polyurethanes obtained by reaction of cyclic (alicyclic or aromatic) isocyanates and polyols. Polymers having other cyclic (aromatic, heterocyclic, or alicyclic) groups or polymers having halogen atoms other than fluorine as substituents also have high refractive index. You may use the polymer formed by the superposition | polymerization reaction of the monomer which introduced the double bond and enabled radical hardening.

In order to obtain a higher refractive index, inorganic fine particles may be dispersed in the polymer binder. It is preferable that the refractive index of an inorganic fine particle is 1.80-2.80. The inorganic fine particles are preferably formed of an oxide or sulfide of a metal. Examples of the metal oxides or sulfides include titanium oxide (for example, mixed crystals of rutile, rutile / anatase, anatase, amorphous structure), tin oxide, indium oxide, zinc oxide, zirconium oxide, zinc sulfide, and the like. Among these, titanium oxide, tin oxide and indium oxide are particularly preferable. The inorganic fine particles are mainly composed of oxides or sulfides of these metals, and may also contain other elements. A main component means the component with most content (weight%) among the components which comprise particle | grains. Examples of other elements include Ti, Zr, Sn, Sb, Cu, Fe, Mn, Pb, Cd, As, Cr, Hg, Zn, Al, Mg, Si, P, S and the like. Inorganic materials that can be dispersed in a solvent or form liquids, such as alkoxides of various elements, salts of organic acids, coordination compounds (e.g. chelate compounds), active inorganic compounds A medium and high refractive index layer can also be formed using a polymer.

The surface of the antireflection layer can be given an antiglare function (a function of scattering incident light from the surface to prevent the appearance of the surroundings of the film from being reflected on the surface of the film). For example, antiglare function can be achieved by forming fine unevenness on the surface of the transparent film to form an antireflection layer on the surface, or by forming an antireflection layer on the surface and then forming the unevenness on the surface by using an embossing roll. The branch can obtain an antireflection layer. An antireflection layer having an antiglare function generally has a haze of 3 to 30%.

The hard coat layer has a hardness higher than that of the transparent support. It is preferable that a hard-coat layer contains the polymer bridge | crosslinked. The hard coat layer can be formed using an acryl, urethane or epoxy polymer, oligomer or monomer (for example, ultraviolet curable resin). It is also possible to form a hard coat layer from a silica-based material.

A lubricating layer may be formed on the surface of the antireflection layer (low refractive index layer). The lubricating layer has a function of imparting sliding property to the surface of the low refractive index layer and improving scratch resistance. The lubricating layer can be formed using polyorganosiloxane (for example silicone oil), natural wax, petroleum wax, higher fatty acid metal salt, fluorine-based lubricant or derivatives thereof. It is preferable that the thickness of a lubrication layer is 2-20 nm.

When forming a light absorbing layer separately from each layer mentioned above, the indole compound of this invention may be used as it is, or a binder may be used. As the binder, for example, natural polymer materials such as gelatin, casein, starch, cellulose derivative, alginic acid, or polymethyl methacrylate, polyvinyl butyral, polyvinylpyrrolidone, polyvinyl alcohol, polyvinyl chloride, styrene Synthetic polymer materials such as butadiene copolymer, polystyrene, polycarbonate, polyamide, polyurethane, polyester, and polyurea.

Said primary coating layer, antireflection layer, hard coat layer, lubricating layer, light absorbing layer and the like can be formed by a general coating method. As a coating method, the deep coating method, the air knife coating method, the curtain coating method, the roller coating method, the wire bar coating method, the gravure coating method, the hopper using the hopper Extrusion coating method (described in the specification of US Pat. No. 2,268,942), and the like. Two or more layers may be formed by simultaneous application. For the simultaneous coating method, for example, the specifications of U.S. Pat.No.2761791, U.S. Pat.No.2941898, U.S. Pat.No.3508947, U.S.Patent No.3526528, and Harasaki Yuki Co., Ltd., page 253 ( Published by Asakura Bookstore in 1973).

Next, the optical recording material of the present invention will be described.

The optical recording material of the present invention contains the indole compound of the present invention and is used for forming the optical recording layer of the optical recording medium, and can be applied to various optical recording media according to the light absorption characteristics of the indole compound. . Of the optical recording materials of the present invention, particularly suitable for optical disks for short wavelength lasers having a wavelength of 380 nm to 420 nm, the indole compound containing a maximum absorption wavelength? Max of 320 to 420 nm in the light absorption characteristic in solution state It is in the range of. Regarding the absorption intensity, if the ε at λ max is smaller than 1.0 × 10 ⁴ , the recording sensitivity may decrease, so 1.0 × 10 ⁴ or more is preferable. (Lambda) max and (epsilon) in the solution state of the said indole compound can be performed by selecting the density | concentration of a sample solution, the solvent used for a measurement, etc. according to a conventional method.

The method for forming the optical recording layer of the optical recording medium using the optical recording material of the present invention containing the above indole compound is not particularly limited. Generally, lower alcohols, such as methanol and ethanol; Ether alcohols such as methyl cellosolve, ethyl cellosolve, butyl cellosolve and butyl diglycol; Ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone and diacetone alcohol; esters such as ethyl acetate, butyl acetate and methoxy ethyl acetate; Fluorinated alcohols such as acrylic acid esters such as ethyl acrylate and butyl acrylate, and 2,2,3,3-tetrafluoropropanol; Hydrocarbons such as benzene, toluene and xylene; Wet coating method in which a solution obtained by dissolving the indole compound and various compounds of the present invention in an organic solvent such as chlorinated hydrocarbons such as methylene dichloride, dichloroethane and chloroform is applied on a substrate by spin coating, spraying or dipping. , Vapor deposition method, sputtering method and the like.

The optical recording layer is formed as a thin film, and the thickness thereof is usually 0.001 to 10 mu m, preferably in the range of 0.01 to 5 mu m.

In addition, the content of the indole compound of the present invention in the optical recording material of the present invention is preferably 10 to 100% by mass in the solid content contained in the optical recording material of the present invention. The optical recording layer is preferably formed so as to contain 50 to 100% by mass of the indole compound represented by the general formula (I) in the optical recording layer, and in order to form an optical recording layer having such an indole compound content, The optical recording material of more preferably contains 50 to 100% by mass of the indole compound represented by the general formula (I), based on the solid content contained in the optical recording material of the present invention.

The optical recording material of the present invention is, in addition to the indole compound of the present invention, if necessary, a cyanine compound, an azo compound, a phthalocyanine compound, an oxonol compound, a squarylium compound, a styryl compound, a porpine compound, an azlenium compound , Croconic methine compounds, pyryllium compounds, thiopyryllium compounds, triarylmethane compounds, diphenylmethane compounds, tetrahydrocholine compounds, indophenol compounds, anthraquinone compounds, naph Compounds usable for ordinary optical recording layers such as toquinone compounds, xanthene compounds, thiazine compounds, acridine compounds, oxazine compounds, spiropyran compounds, fluorene compounds, and rhodamine compounds; Resins such as polyethylene, polyester, polystyrene and polycarbonate; Surfactants; Antistatic agent; Lubricant; Flame retardant; Radical scavengers such as hindered amines; Pit formation promoters such as ferrocene derivatives; Dispersants; Antioxidants; Crosslinking agents; You may contain a light fastener. The optical recording material of the present invention may contain an aromatic nitro compound, an aluminum compound, an iminium compound, a bisiminium compound, a transition metal chelate compound, or the like as a quencher such as singlet oxygen, or a quencher anion may be used. . In the optical recording material of the present invention, it is preferable that these various compounds are used in an amount within the range of 0 to 50% by mass in the solid content contained in the optical recording material of the present invention.

The material of the substrate forming such an optical recording layer is not particularly limited as long as it is substantially transparent to writing (writing) light and reading (reproducing) light. For example, polymethyl methacrylate, polyethylene terephthalate, poly Resin, such as carbonate, glass, etc. are used. In addition, the shape may use any shape, such as a tape, a drum, a belt, and a disk, according to a use.

On the optical recording layer, a reflective film may be formed by evaporation or sputtering using gold, silver, aluminum, copper, or the like, or a protective layer may be formed by acrylic resin, ultraviolet curable resin, or the like.

<Example>

Hereinafter, the present invention will be described in more detail as examples and comparative examples. However, the present invention is not limited at all by the following examples and the like.

Example 1 Synthesis of Compound No. 1

Into a nitrogen-substituted reaction flask, 10 ml of dimethylformamide (DMF) and 80 ml of chloroform were added, and 6.91 g (45.1 mmol) of phosphorus oxychloride was added dropwise under ice cooling, followed by stirring for 1 hour under ice cooling. What dissolved 3.94 g (30.Ommol) of 1-methylindole in 40 ml of chloroforms was dripped under ice cooling, and it heated and refluxed for 3 hours. After cooling to room temperature, the reaction solution was slowly added dropwise to a 400 ml aqueous solution of 23.1 g (126 mmol) of potassium hexafluorophosphate, followed by stirring at room temperature for 2 hours. The precipitate was separated by filtration, and washed with 200 ml of methanol at room temperature for 30 minutes. 9.32 g (yield 93.4%) of pink solids were obtained through filtration and drying. It was confirmed that the obtained pink solid is compound No. 1 which is a target object. The analysis results of Compound No. 1 obtained are shown below.

(1) ¹ H-NMR (ppm, DMSO solvent)

3.57 (s; 3H), 3.74 (s; 3H), 4.01 (s; 3H), 7.39-7.50 (m; 2H), 7.26-7.65 (m; 1H), 8.00-8.10 (m; 1H), 8.70 ( s; 1 H), 9.12 (s; 1 H)

(2) IR absorption (cm ^-l )

3168, 1647, 1536, 1466, 1402, 1349, 1256, 1113, 838, 758

(3) UV absorption measurement (acetone solvent)

λ max; 345.Onm, ε; 1.86 × 10 ⁴ (concentration 6.68 × 10 ^-6 mol / ℓ)

(4) Decomposition temperature (TG-DTA: 100 ml / min in nitrogen stream, elevated temperature 10 deg. C / min)

295.8 ° C .; Melting point, 326.7 ° C .; Mass reduction start point

Example 2 Synthesis of Compound No. 2

Into a nitrogen-substituted reaction flask, 100 ml of DMF and 80 ml of chloroform were added, 6.90 g (45.Ommol) of phosphorus oxychloride was added dropwise under ice-cooling, followed by stirring for 1 hour under ice-cooling. What melt | dissolved 6.22 g (30.Ommol) of 1-methyl- 2-phenylindole in 40 ml of chloroforms was dripped under ice-cooling, and it heated and refluxed for 3 hours. After cooling to room temperature, the reaction solution was slowly added dropwise to a 400 ml aqueous solution of 20.0 g (109 mmol) of potassium hexafluorophosphate, followed by stirring at room temperature for 30 minutes. The aqueous layer was removed, 400 ml of water was added, the mixture was stirred at room temperature for 30 minutes, the precipitate was separated by filtration, and 150 ml of ethanol was stirred at room temperature for 30 minutes to wash. Filtration and drying yielded an off-white solid. Recrystallization was carried out from acetonitrile / ethanol mixed solvent to obtain 5.06 g (yield 41.5%) of an off-white solid. It was confirmed that the obtained off-white solid is compound No. 2 which is a target object. The analysis results of Compound No. 2 obtained are shown below.

(1) ¹ H-NMR (ppm, DMSO solvent)

3.53 (s; 3H), 3.68 (s; 3H), 3.82 (s; 3H), 7.45-7.55 (m; 2H), 7.58-7.75 (m; 5H), 7.83 (d; 1H, J = 7.8㎐) , 7.88 (d; 1H, J = 7.6 Hz), 8.51 (s; 1H)

(2) IR absorption (cm ^-l )

3430, 1656, 1490, 1474, 1463, 1391, 1120, 842, 795, 754, 705

(3) UV absorption measurement (acetone solvent)

λ max; 348.5 nm, epsilon; 1.74 × 10 ⁴ (concentration 1.93 × 10 ^-6 mol / ℓ)

(4) Decomposition temperature (TG-DTA: 100 ml / min in nitrogen stream, elevated temperature 10 deg. C / min)

162.6 ° C .; Melting point, 332.9 ° C .; Mass reduction start point

Example 3 Synthesis of Compound No. 3

In a nitrogen-substituted reaction flask, 15 g (95.4 mmol) of N, N-n-dibutylformamide and 5.21 g (34.O mmol) of phosphorus oxychloride were added under ice-cooling, and the mixture was stirred for 1 hour under ice-cooling. 2.62 g (20.Ommol) of 1-methylindole were added under ice-cooling, and stirred at 100 ° C for 3 hours. After cooling to room temperature, N, N-n-dibutylformamide was evaporated off, and then 15.3 g (95.4 mmol) of potassium hexafluorophosphate was added and mixed uniformly. After 150 ml of water was added and stirred at room temperature for 30 minutes, the precipitate was separated by filtration, stirred for 100 minutes at room temperature using 100 ml of methanol, again 50 ml of water was added, and the mixture was stirred at room temperature for 30 minutes to wash. It was. Filtration and drying yielded an ocher solid. Recrystallization was carried out from an acetonitrile / methanol mixed solvent, followed by filtration and drying to obtain 2.90 g (yield 34.8%) of a pale pink solid. It was confirmed that the obtained pale pink solid was compound No. 3 which is a target object. The analysis results of Compound No. 3 obtained are shown below.

(1) ¹ H-NMR (ppm, DMSO solvent)

0.96 (t; 3H; J = 7.3 kPa), 0.97 (t; 3H; J = 7.3 kPa), 1.36 (tq; 2H; J = 7.6, 7.3 kPa), 1.52 (tq; 2H; J = 7.8, 7.6 kPa ), 1.70-1.89 (m; 4H), 3.85-3.99 (m; 4H), 4.05 (s; 3H), 7.45 (dd; 1H, J = 6.6, 3.9 kPa), 7.46 (dd; 1H, J = 6.6 , 3.7㎐), 7.68-7.80 (m; 1H), 8.08-8.20 (m; 1H), 8.56 (s; 1H), 9.08 (s; 1H)

(2) IR absorption (cm ^-l )

2955, 2874, 1639, 1532, 1476, 1352, 1256, 1114, 834, 751

(3) UV absorption measurement (chloroform solvent)

λ max; 357. 0 nm, ε; 2.04 × 10 ⁴ (concentration 5.64 × 10 ^-6 mol / ℓ)

(4) Decomposition temperature (TG-DTA: 100 ml / min in nitrogen stream, elevated temperature 10 deg. C / min)

179.7 ° C .; Melting point, 307.8 ° C .; Mass reduction start point

Example 4 Synthesis of Compound No. 4

In a nitrogen-substituted reaction flask, 15 g (95.4 mmol) of N, N-n-dibutylformamide and 5.21 g (34.O mmol) of phosphorus oxychloride were added under ice-cooling, and the mixture was stirred for 1 hour under ice-cooling. 6.22 g (30.Ommol) of 1-methylindole were added under ice-cooling, and stirred at 100 ° C for 4 hours. After cooling to room temperature, N, N-n-dibutylformamide was evaporated off, and then 25.0 g (132 mmol) of potassium trifluoromethanesulfonate was added and mixed uniformly. After adding 150 ml of water and performing ultrasonic irradiation for 30 minutes at room temperature, the precipitate was separated by filtration. Recrystallization was carried out from an ethanol / diethyl ether mixed solvent, followed by filtration and drying to obtain 4.64 g (yield 55.1%) of a pale yellow solid. It was confirmed that the obtained pale yellow solid was compound No. 4 which is a target object. The analysis results of Compound No. 4 obtained are shown below.

(1) ¹ H-NMR (ppm, DMSO solvent)

0.94 (t; 3H; J = 6.6 μs), 0.96 (t; 3H; J = 7.1 μs), 1.35 (tq; 2H; J = 7.6,7.6 μs), 1.51 (tq; 2H; J = 7.6,7.6 μs ), 1.70-1.85 (m; 4H), 3.85-3.95 (m; 4H), 4.05 (s; 3H), 7.35-7.50 (m; 2H), 7.65-7.80 (m; 1H), 8.05-8.20 (m) ; 1H), 8.58 (s; 1H), 9.09 (s; 1H)

(2) IR absorption (cm ^-l )

2960, 2874, 1624, 1588, 1476, 1464, 1430, 1265, 1153, 1032, 965

(3) UV absorption measurement (chloroform solvent)

λ max; 356.5 nm, epsilon; 1.84 × 10 ⁴ (concentration 9.89 × 10 ^-6 mol / ℓ)

(4) Decomposition temperature (TG-DTA: 100 ml / min in nitrogen stream, elevated temperature 10 deg. C / min)

110.3 ° C .; Melting point, 287.1 ° C .; Mass reduction start point

Example 5 Synthesis of Compound No. 5

In a nitrogen-substituted reaction flask, 22.5 g (143 mmol) of N, N-n-dibutylformamide and 7.82 g (51.O mmol) of phosphorus oxychloride were added under ice-cooling, and the mixture was stirred for 1 hour under ice-cooling. 6.08 g (18.4 mmol) of 1- (3,5-bistrifluoromethylphenyl) indole were added under ice-cooling, followed by stirring at 100 ° C for 4 hours. After cooling to room temperature, N, N-n-dibutylformamide was evaporated off, and then 50.0 g (272 mmol) of potassium hexafluorophosphate was added and mixed uniformly.

After adding 1 L of water and stirring at room temperature for 30 minutes, the aqueous layer was removed, and after washing for 30 minutes using 1 L of ethanol, the precipitate was separated by filtration. Recrystallization was carried out from an acetone / ethanol mixed solvent, followed by filtration and drying to obtain 2.75 g (yield 24.3%) of colorless and transparent acicular crystals. It was confirmed that the obtained colorless transparent needle crystal was compound No. 5 which is a target object. The analysis results of Compound No. 5 obtained are shown below.

(1) ¹ H-NMR (ppm, DMSO solvent)

0.96 (t; 3H; J = 7.6 kPa), 0.99 (t; 3H; J = 7.1 kPa), 1.40 (tq; 2H; J = 7.3, 7.1 kPa), 1.48 (tq; 2H; J = 7.6, 7.6 kPa ), 1.78-1.95 (m; 4H), 4.05 (t; 2H; J = 7.6 μs), 4.11 (t; 2H; J = 7.8 μs), 7.51 (dd; 1H; J = 8.5,7.1 μs), 7.55 (dd; 1H; J = 7.8,7.1 Hz), 7.64 (d; 1H; J = 8.3 Hz), 8.26 (d; 1H; J = 7.6 Hz), 8.41 (s; 1H), 8.60 (s; 2H) , 8.83 (s; 1H), 9.34 (s; 1H)

(2) IR absorption (cm ^-l )

2967, 2880, 1646, 1522, 1475, 1360, 1282, 1230, 1192, 1146, 843, 825, 762

(3) UV absorption measurement (chloroform solvent)

λ max; 354.5 nm, ε; 1.92 × 10 ⁴ (concentration 6.87 × 10 ^-6 mol / ℓ)

(4) Decomposition temperature (TG-DTA: 100 ml / min in nitrogen stream, elevated temperature 10 deg. C / min)

183.3 ° C .; Melting point, 297.5 ° C .; Mass reduction start point

Example 6 Synthesis of Compound No. 6

In a nitrogen-substituted reaction flask, 22.5 g (143 mmol) of N, N-n-dibutylformamide and 7.82 g (51.O mmol) of phosphorus oxychloride were added under ice-cooling, and the mixture was stirred for 1 hour under ice-cooling. 6.22 g (30.Ommol) of 1-methyl-2-phenylindole were added under ice-cooling and stirred at 100 ° C for 4 hours. After cooling to room temperature, N, N-n-dibutylformamide was evaporated off, and then 50.0 g (272 mmol) of potassium hexafluorophosphate was added and mixed uniformly. After adding 1 L of water and stirring for 30 minutes at room temperature, the precipitate was filtered off. Recrystallization was carried out from an acetone / ethanol mixed solvent, followed by filtration and drying to obtain 3.02 g (yield 20.4%) of a pale green solid. It was confirmed that the obtained pale green solid was Compound No. 6 which is a target substance. The analysis results of Compound No. 6 obtained are shown below.

(1) ¹ H-NMR (ppm, DMSO solvent)

0.80 (t; 3H; J = 7.3 kPa), 0.90 (t; 3H; J = 7.3 kPa), 1.20 (tq; 2H; J = 7.6,7.6 kPa), 1.30 (tq; 2H; J = 7.6, 7.6 kPa ), 1.65-1.79 (m; 4H), 3.82 (s; 3H), 3.89 (t; 2H; J = 6.8 Hz), 3.91 (t; 2H; J = 6.8 Hz), 7.49 (dd; 1H; J = 7.2,7.2 Hz), 7.53 (dd; 1H; J = 7.1, 7.1 Hz), 7.57-7.63 (m; 2H), 7.64-7.77 (m; 3H), 7.80 (d; 1H; J = 7.8 Hz), 7.85 (d; 1H; J = 7.8 Hz), 8.54 (s; 1H)

(2) IR absorption (cm ^-l )

2960, 2935, 2874, 1651, 1477, 1464, 1404, 1368, 1086, 838, 802, 750

(3) UV absorption measurement (chloroform solvent)

λ max; 352.5 nm, epsilon; 2.48 × 10 ⁴ (concentration 4.07 × 10 ^-6 mol / ℓ)

(4) Decomposition temperature (TG-DTA: 100 ml / min in nitrogen stream, elevated temperature 10 deg. C / min)

100.4 ° C .; Melting point, 304.9 ° C .; Mass reduction start point

Example 7 Synthesis of Compound No.21

In a nitrogen-substituted reaction flask, 10 ml of N, N-n-dimethylformamide, 80 ml of chloroform, and 6.74 g (44.Ommol) of phosphorus oxychloride were added to the reaction flask under ice-cooling, followed by stirring for 1 hour under ice-cooling. A 40 mL solution of 10.5 g (29.3 mmol) of chloroform in 1-propylferrocenyl indole was added under ice-cooling, and the mixture was heated to reflux for 3.5 hours. The mixture was cooled to room temperature, and slowly added dropwise to a 500 ml aqueous solution of 23.5 g (127 mmol) of potassium hexafluorophosphate, followed by stirring at room temperature for 1 hour. The precipitate was separated by filtration and dried to obtain 16.2 g (yield 99.4%) of a dark brown solid. It was confirmed that the obtained dark brown solid is compound No. 21 which is a target object. The analysis results of the obtained Compound No. 21 are shown below.

(1) ¹ H-NMR (ppm, DMSO solvent)

1.48 (dt; 2H; J = 7.3, 7.3 Hz), 1.90 (dt; 2H; J = 7.3, 7.3 Hz), 2.32 (t; 2H; J = 7.6 Hz), 3.61 (s; 3H), 3.74 (s ; 3H), 4.03 (s; 5H), 3.98-4.05 (m; 4H), 4.44 (t; 2H; J = 7.3 kPa), 7.35-7.50 (m; 2H), 7.81 (d; 1H; J = 7.1 I), 8.08 (d; 1H; J = 6.8 Hz), 8.76 (s; 1H), 9.17 (s; 1H)

(2) IR absorption (cm ^-l )

1654, 1530, 1404, 1364, 1105, 836

(3) UV absorption measurement (chloroform solvent)

λ max; 353.Onm, ε; 2.10 × 10 ⁴ (concentration 1.59 × 10 ^-5 mol / ℓ)

(4) Decomposition temperature (TG-DTA: 100 ml / min in nitrogen stream, elevated temperature 10 deg. C / min)

200.5 ° C .; Melting point, 284.7 ° C .; Mass reduction start point

Example 8 Synthesis of Compound No. 24

 To the nitrogen-substituted reaction flask, 43.6 g (277 mmol) of N, N-n-dibutylformamide and 13.3 g (87.1 mmol) of phosphorus oxychloride were added to the reaction flask with ice, and the mixture was stirred for 1 hour under ice-cooling. 12.2 g (58.Ommol) of 5-bromo-1-methylindole was added under ice-cooling, and stirred at 100 ° C for 4 hours. After cooling to room temperature, N, N-n-dibutylformamide was evaporated off, and then 58.0 g (315 mmol) of potassium hexafluorophosphate was added and mixed uniformly. After adding 1 L of water and stirring for 30 minutes at room temperature, the precipitate was filtered off. Recrystallization was carried out from acetone / methanol mixed solvent, and filtration and drying yielded 18.9 g (yield 65.8%) of a pale yellow solid. It was confirmed that the obtained pale yellow solid was compound No. 24 which is a target object. The analysis results of Compound No. 24 obtained are shown below.

(1) ¹ H-NMR (ppm, DMSO solvent)

0.95 (t; 3H; J = 7.3 kPa), 0.96 (t; 3H; J = 7.3 kPa), 1.36 (tq; 2H; J = 7.3, 7.8 kPa), 1.50 (tq; 2H; J = 7.6, 7.8 kPa ), 1.72-1.87 (m; 4H), 3.91 (t; 4H; J = 7.1 μs), 4.04 (s; 3H), 7.59 (dd; 1H; J = 1.7, 8.8 μs), 7.71 (d; 1H; J = 8.8 Hz), 8.41 (d; 1 H; J = 1.7 Hz), 8.58 (s; 1 H), 9.11 (s; 1 H)

(2) IR absorption (cm ^-l )

2964, 1638, 1530, 1449, 1353, 1253, 1123, 838

(3) UV absorption measurement (chloroform solvent)

λ max; 354. 0 nm, ε; 2.14 × 10 ⁴ (concentration 1.01 × 10 ^-5 mol / ℓ)

(4) Decomposition temperature (TG-DTA: 100 ml / min in nitrogen stream, elevated temperature 10 deg. C / min)

161.7 ° C .; Melting point, 313.8 ° C .; Mass reduction start point

Example 9 Synthesis of Compound No. 23

2.06 g (4.18 mmol) of Compound No. 24 obtained in Example 8 was dissolved in 20 ml of acetone, and 5.0 mmol of the triethylamine salt of the anion represented by the formula [C] was added dropwise into 162 ml of acetone. It was heated to reflux for time. After cooling to room temperature, the reaction was slowly added dropwise to 800 ml of water and stirred at room temperature for 14 hours. The precipitated solid was separated by filtration, washed with acetone and dried to obtain 4.18 g (yield 93.7%) of reddish brown solid. It was confirmed that the obtained reddish-brown solid is compound No. 23 which is a target object. The analysis results of Compound No. 23 obtained are shown below.

(1) ¹ H-NMR (ppm, DMSO solvent)

0.95 (t; 6H; J = 7.1 μs), 1.01 (t; 12H; J = 7.1 μs), 1.36 (tq; 2H; J = 7.3,7.3 μs), 1.48 (tq; 2H; J = 7.3,7.3 μs ), 1.72-1.85 (m; 4H), 3.29 (q; 8H; J = 6.8 Hz), 3.89 (t; 4H; J = 7.6 Hz), 4.00 (s; 3H), 5.74 (d; 2H; J = 2.4 kV), 6.35 (dd; 2H; J = 2.7, 9.5 kPa), 6.55 (d; 2H; J = 9.3 kPa), 7.58 (dd; 1H; J = 1.7, 8.8 kPa), 7.64 (d; 2H; J = 9.3 kV), 7.69 (d; 1 H; J = 8.8 kV), 7.84 (dd; 2 H; J = 2.9, 9.3 kV), 8.39 (d; 1 H; J = 1.7 kV), 8.54 (s; 1 H) , 9.00 (d; 2H; J = 2.9 Hz), 9.08 (s; 1H)

(2) IR absorption (cm ^-l )

2975, 1611, 1578, 1459, 1320, 1283, 1262, 1141

(3) UV absorption measurement (chloroform solvent)

λ max; 357.5 nm, ε; 3.95 × 10 ⁴

541.5 nm, epsilon; 6.20 × 10 ⁴ (concentration 2.18 × 10 ^-6 mol / ℓ)

(4) Decomposition temperature (TG-DTA: 100 ml / min in nitrogen stream, elevated temperature 10 deg. C / min)

216.8 ° C .; Melting point, 258.9 ° C .; Mass reduction start point

Example 10 Preparation of Optical Filter Including Adhesive Layer

A UV varnish was prepared by the following formulation, and the UV varnish was applied to a 188 μm-thick PET film subjected to reverse adhesion by bar coater # 9, followed by drying at 100 ° C. for 10 minutes. Then, 100 mJ of ultraviolet-rays were irradiated with the high pressure mercury lamp with an infrared cut film filter, and the optical filter which has a film layer (adhesive layer) of about 5 microns of cured film thickness on the PET film was obtained. (Lambda) max was 353 nm when this optical filter was measured with the ultraviolet visible near-infrared spectrophotometer V-570 by Nippon Bunko Corporation.

(combination)

Compound No. 4 2.0 mg

20 g of acrylic pressure-sensitive adhesives (DB5541: DIA BODO CORPORATION)

Methyl ethyl ketone 80g

Example 11 Fabrication of Optical Filter

A UV varnish was prepared by the following formulation, and the UV varnish was applied to a 188 μm-thick PET film subjected to reverse adhesion by bar coater # 9, and then dried at 100 ° C. for 10 minutes. Thereafter, 100 mJ of ultraviolet rays were irradiated with a high pressure mercury lamp with an infrared ray blocking film filter to obtain an optical filter having a film layer having a cured film thickness of about 5 microns on a PET film. (Lambda) max was 354 nm when this optical filter was measured with the ultraviolet visible near-infrared spectrophotometer V-570 by Nihon Bunco.

(combination)

Adeka optomer KRX-571-65 100 g

(UV cured resin made by Adeka Co., Ltd., resin weight 80% by weight)

Compound No. 5 2.0 mg

Methyl ethyl ketone 60g

Example 12 Preparation of Optical Recording Material and Optical Recording Medium and Evaluation of Optical Recording Medium

Compound No. 4 obtained in Preparation Example 4 was dissolved in 2,2,3,3-tetrafluoropropanol so that the concentration of Compound No. 4 was 1.0% by mass, and 2,2,3,3-tetrafluoro An optical recording material was obtained as a propanol solution. Titanium chelate compound (T-50: manufactured by Nippon Soda Co., Ltd.) was applied and hydrolyzed to form a base layer (0.01 μm) on a 12 cm diameter polycarbonate disc substrate, the optical recording material described above. Was applied by spin coating to form an optical recording layer having a thickness of 100 nm to obtain an optical recording medium. With respect to the optical recording medium, the absorption UV spectrum of the thin film and the UV spectrum of the reflected light having an incident angle of 5 ° were measured. The absorption lambda max was 353 nm and the reflected light lambda max was 382 nm.

The filter using the indole compound of the present invention had an absorption maximum at a specific wavelength (340 to 390 nm) (Examples 10 and 11), and it was confirmed that it was suitable as an ultraviolet absorber for an optical filter.

Further, the optical recording medium having the optical recording layer formed of the optical recording material containing the indole compound of the present invention has an absorption maximum of reflected light at a specific wavelength (340 to 390 nm) (Example 12). In the reproduction mode of the optical recording medium represented by the optical disk, the presence or absence of recording is detected by the difference in the amount of laser wavelengths with respect to the reflected light reflected by the laser light on the optical recording medium. It is more preferable that the greater the absorption intensity is shown in the vicinity of the wavelength of the laser light. Therefore, the optical recording material of the present invention containing the indole compound of the present invention is suitable as an optical recording material used for forming an optical recording layer of an optical recording medium using 405 nm laser light such as an optical disk for short wavelength laser.

Evaluation Example 1-1 to 1-5 and Comparative Evaluation Example 1-1 Evaluation of light resistance of the compound represented by the general formula (I).

Light resistance evaluation was performed about the compound No.21, No.23, No.24 which were obtained in Examples 7-9, and the comparative compound 1.

First, a 2,2,3,3-tetrafluoropropanol solution was prepared by dissolving the compound of the present invention in 1,2% by mass in 2,2,3,3-tetrafluoropropanol, and the resulting solution was 20x20. The test piece was prepared by apply | coating by the spin-coating method for 2000 rpm and 60 second on the polycarbonate plate of mm. Evaluation was performed by irradiating 55,000 lux of light to the said test piece, and irradiating for 24 hours and 150 hours, respectively, and measuring the absorbance residual ratio in (lambda) max of the UV absorption spectrum before irradiation. In addition, in Table 1, as a combined substance, 0.1 mass% of the diimmonium compound or dithiol compound shown in following [Formula 8] of a 2,2,3,3- tetrafluoropropanol solution is It was dissolved and used as much as possible. The results are shown in [Table 1].

As is apparent from Table 1, the compound represented by the general formula (I) of the present invention has a high absorbance persistence even after 150 hours of irradiation, and is also irradiated even when a diimnium compound or a dithiol compound is used in combination. Even after 150 hours, no decrease in absorbance persistence was observed. On the other hand, the comparative compound showed a decrease in absorbance persistence after 24 hours of irradiation, and a remarkable decrease in absorbance persistence after 150 hours of irradiation.

The present invention can provide a novel indole compound suitable as an optical element. Further, the optical filter using the indole compound is suitable as an optical filter for an image display device, and the optical recording material containing the indole compound is suitable for forming the optical recording layer of the optical recording medium.

Claims (5)

An indole compound characterized by the following general formula (I). [Formula 1]

(In formula, R <^1> and R <^2> respectively independently represents a hydrogen atom, a hydrocarbon group of 1-30 carbon atoms, or a substituent represented by the following general formula (II), R <^3> and R <^4> respectively independently, An alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or an aryl group having 6 to 30 carbon atoms, and R ⁵ , R ⁶ , R ⁷ and R ⁸ each independently represent a hydrogen atom and carbon; A hydrocarbon group having 1 to 30 atoms, a halogen atom, a hydroxyl group, a nitro group, a cyano group, NHR or NR'R '', and each of R, R 'and R''is independently 1 to 10 carbon atoms. An alkyl group, R 'and R''may be linked to each other to form a ring, and R ⁵ and R ⁶ , R ⁶ and R ⁷ , R ⁷ and R ⁸ may be linked to each other to form a ring; An ^{q -} represents q valent anion, q represents 1 or 2, and p represents the coefficient of maintaining charge neutral. [Formula 2]

(Wherein R ^a to R ⁱ each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, the methylene group in the alkyl group may be substituted with -0- or -C0-, and Z is a direct bond or It represents an alkylene group having 1 to 8 carbon atoms which may have a substituent, and the methylene group in the alkylene group is -0-, -S-, -C0-, -CO0-, -OC0-, -S0 _2- , -NH -, -CONH-, -NHC0-, -N = CH- or -CH = CH- may be substituted, and M represents a metal atom.) The compound of claim 1, wherein in formula (I), R ¹ is a hydrocarbon group having 1 to 30 carbon atoms, R ² is a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms, and R ³ is carbon An alkyl group having 1 to 10 atoms, and R ⁴ is an alkyl group having 1 to 10 carbon atoms. An optical filter comprising the indole compound according to claim 1 or 2. The optical filter according to claim 3, which is for an image display device. An optical recording material comprising the indole compound according to claim 1 or 2 used in the optical recording layer of an optical recording medium having an optical recording layer formed on a substrate.